Arthroscopic Treatment of Acute Ankle Fractures and Postfracture Problems



Arthroscopic Treatment of Acute Ankle Fractures and Postfracture Problems


SINA KASRAEIAN

RICHARD D. FERKEL



Fractures involving the ankle joint are among the most common fractures and can occur in all age groups.1, 2 Evidence of healed ankle fractures has been found in the remains of ancient Egyptian mummies.3 Hippocrates suggested that closed fractures be reduced by traction of the foot but that open fractures should not be reduced or the patient would die from “inflammation and gangrene” within several days.4, 5 Unfortunately, until the mid-18th century, there were few advances in the understanding and treatment of ankle injuries. Closed treatment of ankle fractures was recommended in the 18th and 19th centuries.6, 7, 8 Subsequently, interest in operative treatment of ankle injuries arose due to the unsatisfactory results of closed treatment of some fractures, as well as the evolution of x-rays, anesthesia, and surgical asepsis.9 In 1894, Lane was the first to recommend surgical treatment to anatomically reduce fractures of the ankle.10, 11 In a series of articles in the 1950s, Lauge-Hansen developed a classification system based on clinical, radiographic, and experimental observations.12, 13, 14, 15, 16 Subsequently, Weber developed a different classification system modified from Danis, which was based on the level of fibular fracture.17, 18, 19, 20

Although the long-term results of ankle fractures treated in either closed or open fashion have significantly improved over the last several decades, problems still exist with postfracture stiffness, pain, swelling, and discomfort. Continued problems, including the development of posttraumatic arthritis, soft tissue impingement, and articular fibrosis, can be potentially attributed to residual articular surface incongruity, unappreciated osteochondral defects, and soft tissue injuries.21, 22, 23, 24, 25, 26, 27, 28, 29, 30 In the past, the extent of intra-articular damage had not been fully appreciated because there was no practical method to directly visualize the entire joint. Even with extensive open reduction and internal fixation, not all intra-articular areas of the ankle are well seen. The excellent results with arthroscopic reduction and stabilization of tibial plateau31, 32 and distal radius33, 34 fractures stimulated the development of similar techniques in the ankle.35, 36


ADVANTAGES OF ARTHROSCOPY

Arthroscopy allows thorough visualization of the entire ankle joint and direct assessment of bone, cartilage, ligaments, and soft tissue structures (intra-articular pathology) without the morbidity associated with more invasive surgical exposures.37 It provides a way of lavaging the joint and removing any loose bodies and debris resulted from the injury. It can also assist in reduction and internal fixation of certain ankle fractures that are amenable to arthroscopic or arthroscopic-assisted treatment. Moreover, it allows assessment and verification of the congruity of the articular surfaces after internal fixation. In addition, arthroscopy can be used to address chronic ankle pain and dysfunction resulting from previous tra uma.29, 35, 36, 38, 39, 40, 41

Disadvantages include a relatively steep learning curve, expensive and complex instrumentation, and possibility of equipment failure, in addition to the inherent surgical risks of arthroscopic surgery such as infection, chondral damage, and neurovascular injury.37






ARTICULAR INJURIES ASSOCIATED WITH FRACTURES

Damage to the articular surface of the ankle joint commonly occurs during ankle trauma. Feldman62 reported on eleven (73%) articular injuries (7 talar and 4 tibial lesions) in 15 extra-articular ankle fractures (14 supination-external rotation and 1 pronation-external rotation pattern). Similarly, Hintermann et al.63 demonstrated a 79% rate of articular surface lesions in 288 patients who underwent ankle arthroscopy prior to open reduction and internal fixation of acute fractures; the incidence and severity of the lesions increased with the severity of the injury. Loren and Ferkel44, 64 found 30 (63%) traumatic articular surface lesions (TASLs) (19 talar and 11 tibial lesions) in 48 acute ankle fractures, with the greatest incidence in fractures that disrupted the syndesmosis. In addition, almost all patients were found to have fracture hematoma and debris including 13 (27%) patients who required removal of free fragments.44, 64 Stufkens et al.65 recently published prospective data establishing a strong correlation between intra-articular cartilage injury and the development of posttraumatic ankle arthritis in 109 patients followed for 11 to 15 years after initial injury (Fig. 11-1A-D).







FIGURE 11-1. (Continued) (C, D) Weber type C fracture/subluxation of the ankle with associated lateral TASL. Note the tear of the anterior inferior tibiofibular ligament, interosseous membrane, and deltoid ligament. (A and C—Copyright Richard D. Ferkel, Illustration by Susan Brust.)


PREOPERATIVE PLANNING

Preoperative radiographs should include the standard anterior-posterior, lateral, and mortise views. Occasionally, with osteochondral fractures or triplane fractures, computed tomographic scans are beneficial in identifying fracture patterns. Ideally, arthroscopic evaluation and fracture treatment is done as soon as possible. However, within several hours after injury, edema precludes safe arthroscopic treatment. If significant edema is present, then the ankle fracture is reduced and stabilized in a cast or splint and kept elevated until the swelling resolves—usually in 7 to 14 days. Intermittent pneumatic compression devices may help with edema reduction.66 An indication of edema resolution is the skin “wrinkle test.” Once edema has resolved, proceed with surgical management.44




POSTOPERATIVE CARE

Most uncomplicated fractures remain nonweight bearing for 4 weeks. At 2 to 4 weeks, the reliable patient with stable fixation can be transitioned from splint or cast into a Cam walker or removable splint to allow range of motion exercises. At 4 weeks, progressive weightbearing to tolerance is initiated in either a Cam walker or short leg walking cast.

More complicated or unstable fractures and those with syndesmotic injury may require longer periods of non-weight-bearing treatment. Complex pilon or talus fractures
routinely require up to 3 months or longer before considering weightbearing. Range of motion exercises are initiated as soon as the fracture is mechanically stable in order to minimize stiffness.35, 36, 46


AUTHOR’S PREFERRED METHOD

All intra- and extra-articular fractures should undergo arthroscopy, even if open reduction and internal fixation is planned, to look for loose bodies, osteochondral lesions, ligament and syndesmotic injuries, and other intra-articular pathology. The patient is positioned supine on a radiolucent operating table. A nonsterile tourniquet is placed on the proximal thigh, which rests on a well-padded thigh holder as previously described in Chapter 4. After administration of general, spinal, or regional anesthesia, the lower extremity is prepared, prepped and draped in standard fashion.

Unlike our standard ankle arthroscopy technique, the tourniquet is not used at this time unless excessive bleeding prohibits adequate visualization. In addition, we apply the noninvasive distraction strap but only manually pull on it; only occasionally do we attach the strap to the distraction device, such as in specific cases when the distraction can actually assist in the reduction or can safely increase the joint space without significantly displacing the fracture fragments. All appropriate landmarks are palpated and marked. Note that the superficial peroneal nerve is marked prior to placement of the ankle in the noninvasive distraction device.

The anteromedial portal is established first. The anterolateral portal is then made, with care taken not to injure the superficial peroneal nerve. With gravity inflow through the anterolateral portal, the posterolateral portal is then established using an 18-gauge spinal needle. The inflow is transferred to the posterolateral portal and the joint is lavaged thoroughly to remove all clots, cartilage debris, and bone crumbs (see Chap. 4).

After adequate visualization is attained, the ankle joint is thoroughly examined to assess the fracture site and any associated lesions, including syndesmotic and ligament injuries, chondral defects, and other pathology. After associated injuries are addressed, attention returns to the fracture site. With the camera in the anteromedial portal and instrumentation through the anterolateral portal, the fracture site is evaluated. A probe, Freer elevator, or curette can be placed between the fracture lines in order to disimpact the fracture and remove any debris or interpositioned tissue from the fracture site. The arthroscope should also be transferred to the anterolateral and posterolateral portals in order to visualize the fracture site from different perspectives. At this time, the surgeon must decide if the fracture can be managed arthroscopically. If the fracture cannot be treated arthroscopically, then the intra-articular pathology is treated prior to converting to an open technique. If the fracture is amenable to arthroscopic-assisted techniques, specific fracture patterns are addressed individually, applying the general principles mentioned previously.67


Treatment of Specific Fracture Patterns


Medial Malleolar Fracture

The medial malleolar fracture is usually caused by an avulsion mechanism as the talus is displaced out of the mortise (Fig. 11-2). In addition, a shearing force, such as in an Lauge-Hansen supination-adduction injury, can cause a vertical or oblique medial malleolar fracture, with frequent impaction of the plafond as the talus compresses into the distal tibia.68, 69

The medial plafond at the fracture site should be closely examined for impaction of the articular surface, especially in the Lauge-Hansen supination-adduction injury pattern. Arthroscopy can also aid in the minimally invasive reduction and fixation of the fracture with percutaneously placed screws.

After lavage and assessment of the joint—and addressing associated intra-articular damage—the fracture site is then prepared; any hematoma, debris, or soft tissue potentially impairing visualization or reduction at the fracture site is debrided. Two parallel K-wires or guidewires are percutaneously placed in the medial malleolar fracture fragment aimed perpendicular to the fracture line. The wires are used to manipulate the fragment into an anatomically reduced position under direct visualization with the arthroscope and then advanced across the fracture site into the tibia. After appropriate alignment is confirmed by fluoroscopy, two 4.0-mm cannulated partially threaded cancellous screws are inserted to stabilize the fracture.67, 68, 70 (Fig. 11-3)


Fibular Fracture with Osteochondral Lesion

Chondral and osteochondral injuries occur frequently with ankle fractures—more commonly on the medial or lateral talar dome.62, 64 Lesions can also be found on the tibial plafond.

Articular pathology is addressed prior to turning focus on the fracture (Figs. 11-4 and 11-5). When too small for adequate repair or when devoid of bone, loose cartilaginous pieces and debris should be removed. Full-thickness chondral lesions should be debrided down to the subchondral plate with perpendicular cartilage borders, avoiding beveled edges for better clot retention followed by microfracture and/or drilling (arthroscopic curettes can be useful for this task). Drilling can be performed using transmalleolar or preferably transtalar technique—drilling through the sinus tarsi. A MicroVector or similar drill guide may aid in aiming the K-wire. The surgeon should allow 3- to 5-mm intervals between holes and make sure that the drill penetrates the subchondral plate in order to allow marrow contents and vascular access to the injury site. Loose osteochondral fragments, if of adequate size and quality, can be reduced and stabilized with K-wires, countersunk screws, or preferably bioabsorbable pins35, 44 (refer to Chapter 9). Once the articular lesion is appropriately treated, attention is turned to preparing and treating the fracture site with traditional open reduction and internal fixation technique (Figs. 11-6 and 11-7).






FIGURE 11-2. Medial malleolar fracture. (Illustration by Susan Brust.)






FIGURE 11-3. Medial malleolar fracture. (A) Preoperative x-ray shows displaced medial malleolar fracture with malrotation. (B) Arthroscopic view of left medial malleolar fracture. (C) Intraoperative fluoroscopic view of K-wire insertion used to reduce the fracture. (D) After the fracture is reduced, the K-wires are advanced proximally and the fracture reduction is assessed arthroscopically. (E) Fracture reduction verified with fluoroscopy. (F) Postoperative x-ray at 9 months showed healed medial malleolar fracture.






FIGURE 11-4. Weber type B fracture/subluxation. (Illustration by Susan Brust.)


Posterior Malleolar Fracture

A fracture of the posterior malleolus usually represents an avulsion of the posterolateral distal tibia by the posterior inferior tibiofibular ligament that can occur with external rotation or abduction injury patterns (Fig. 11-8). They occur commonly with Weber B and occasionally Weber C ankle fractures.44, 70 Commonly, reduction of the lateral malleolus reduces and stabilizes the posterior malleolus fragment. When there is persistent intra-articular displacement following reduction and stabilization of the lateral and, when present, medial malleolar fragments, then the posterior malleolar fragment should be addressed surgically. Other indications to fix these fractures include a fracture
gap >2 to 3 mm, nonconcentric joint reduction or posterior subluxation and involvement of >25% of the articular surface, though some argue that routine fixation of all posterior malleolus fractures is necessary to minimize risk of posttraumatic arthrosis.44, 46, 68, 70, 71






FIGURE 11-5. (A, B) Weber type B fracture/subluxation. Arthroscopic view of a Weber type B fracture/subluxation of left ankle. Note the oblique fracture line of the fibula.






FIGURE 11-6. Weber type B fracture/subluxation of the right ankle. (A) As the fracture occurs in the distal fibula, the talus tilts, tearing the deltoid ligament and producing an osteochondral lesion of the medial talar dome. (B) Inversion stress on the ankle joint creates a moment of force (M) that can be resolved along coordinate axes as a vertical (FV) and a horizontal (FH) force. The resultant of these two forces is a shear force (FS), along which the osteochondral lesion occurs. (Redrawn by Susan Brust from Stauffer RN. Intraarticular ankle problems. In: Evarts C. Surgery of the musculoskeletal system, vol. 3. New York, NY: Churchill Livingstone, 1983.)

Application of arthroscopic techniques is ideal for addressing posterior malleolar fractures, as open approaches are relatively invasive and provide limited direct visualization of the joint surface.42, 44, 46 Using the arthroscope in the anteromedial portal, a probe, Freer elevator, or curette is used (through either anterolateral or posterolateral portal) to prepare the fracture site. With the aid of the Freer elevator and percutaneously placed reduction clamps, the fracture is held reduced and temporarily stabilized. Dorsiflexion of the great toe may help during reduction as it forces the flexor hallucis longus against the posterior malleolar fragment46 (Fig. 11-9A-E).

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Sep 25, 2018 | Posted by in RHEUMATOLOGY | Comments Off on Arthroscopic Treatment of Acute Ankle Fractures and Postfracture Problems
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